The Odell Patented Vacuo-Exhaust System

During the late 19th century, the patent was the Holy Grail to the inventor and industrialist. Here in the United States, numerous patents had been sought and granted in application to the pipe organ. Builders were constantly exploring various methods of pneumatically assisted action; it was in this era that Cavaille-Coll began using Barker machines in his instruments in France.

Aside from assisted or pneumatic action, organbuilders had been looking for ways to improve coupling and stop control. These were the first steps to the pipe organ consoles we know today.

John Henry Odell's contribution was the "Vacuo-Exhaust System", a pneumatic chest action system which was an outgrowth of the developments the Odells had been making with pneumatic slider motors. Applied to manual action on a slider chest, divisions could now be coupled together effortlessly, and intra-manual couplers could be more easily introduced, as well as "combination pistons" in the keyslips, programmable via wooden cams in the rear of an organ.

It seemed a revolutionary change at the time, and the Odells wasted no time in putting it into their sales literature, claiming they had rendered the touch of the sometimes unforgiving tracker organ keyboard "as easy and noiseless as that of a piano." Many of the major domestic builders had their own versions of this type of action. Of course, within a decade, tubular-pneumatic actions were considered obsolete; the block tin tubes replaced by wires for electro-pneumatic windchests, the key pallets exchanged for silver wire contacts and buss bars.

You can request a full size scan of the text and drawings of the patent by emailing to us at: info_at_odellorgans.com